1. Field of the Invention
The present invention relates to an image pickup apparatus having a live view function of displaying an object image on a display unit and to a control method and a program for the image pickup apparatus.
2. Description of the Related Art
In the related art, since there are various setting values necessary for photographing in an electronic still camera, it is necessary to change those setting values in accordance with a photographing environment and an attached lens. In case of changing the setting values, it is desirable that while changing the setting values, the user is allowed to easily understand an effect which is obtained by such a change. Particularly, in case of performing AF calibration setting, that is, performing a focusing adjustment value change which corrects a fine defocus amount during auto focus processing, it will be difficult to attain the change of the focusing adjustment value, unless the change process is presented viewably. Therefore, there exists such an apparatus that a live view is started simultaneously with the start of the setting in order to allow the user to easily understand the effect which is obtained by the change.
When the live view is started simultaneously with the start of the setting, since a through image of the live view is displayed in accordance with a Tv value, an Av value, and an ISO value which were set by the user, there is a case where the started live view is not optimum depending on an external environment. In such a case, first, the user himself has to set the Tv value, Av value, and ISO value so that the optimum live view is performed. It is, therefore, troublesome and the Tv value, Av value, and ISO value which have been set at that point of time have to be changed.
Patent Literature 1 (the Official Gazette of Japanese Patent Application Laid-Open No. 2005-260733) discloses the following construction. That is, in a non-depression state in which a release button is not operated, an electronic shutter speed, an aperture value, and a photographing sensitivity which are determined for brightness of an object are set on the basis of a first program diagram which uses an electronic shutter speed adapted to prevent the occurrence of a flicker, in a low brightness range, and in a state in which the release button remains being half-depressed, the aperture value for still image photographing which is determined in response to the half-depressing operation of the release button is set, and the aperture value for still image photographing is applied to an aperture-priority second program diagram to set the electronic shutter speed and the photographing sensitivity which are determined for brightness of the object. However, in such a case, on the contrary, an image to which the Tv value (electronic shutter speed), Av value (aperture value), and ISO value (photographing sensitivity) which were set by the user are reflected is not displayed so long as the release button is not half-depressed. Therefore, a problem occurs in a normal photographing and the troublesomeness is not solved yet.